


Stick around

by mistyegg



Series: 100 Moons (A modern Eruriren series) [1]
Category: Shingeki no Kyojin | Attack on Titan
Genre: Age Regression/De-Aging, Alternate Universe - Modern Setting, Developing Relationship, Established Levi/Erwin Smith, M/M, Non-Sexual Age Play, Polyamory
Language: English
Status: Completed
Published: 2020-10-10
Updated: 2020-10-10
Packaged: 2021-03-08 04:13:32
Rating: Mature
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,067
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/26929459
Author URL: https://archiveofourown.org/users/mistyegg/pseuds/mistyegg
Summary: When Erwin and Levi, a married couple who had moved across the country, become Eren’s neighbors who he somehow manages to bump into at least thrice a week, the brunet knew he was fucked.
Relationships: Levi/Erwin Smith, Levi/Erwin Smith/Eren Yeager
Series: 100 Moons (A modern Eruriren series) [1]
Series URL: https://archiveofourown.org/series/1964908
Comments: 10
Kudos: 150





	Stick around

**Author's Note:**

> i already have so many wips and here i am, throwing out this fic and possibly a few more for a potential eruriren series. why am i like this
> 
> this series DOES contain sexual ageplay (ddlb), however, this part focuses on non-sexual age regression specifically. i know that in the community, there's a difference, but i also know that sometimes it can overlap. if you have issues with it, please approach me respecfully.
> 
> title (loosely ig) taken from 100 moons by savannah saturn

Eren sees Erwin almost daily - the first time they met was in the elevator, on their way out for the day, and have since used the chance to talk to each other for a few minutes, every morning. On days Eren didn’t work, he would go down to pick up his mail early in the morning; it was worth pulling himself out of bed to see Erwin getting ready to go on his routine run, dressed in clothing that left nothing to the imagination.

Levi, at first, was rarely spotted out of the apartment, spending the majority of his time cooped up inside and working. Eren had first met him when the older man had reluctantly come to his apartment door and asked to lend some coffee, saying he couldn’t wait for Erwin to return back from the store or he would pass out right then. Levi was obviously more socially submissive then Erwin and kept to himself more, but his husband forces him out enough to keep his pale skin healthily full of sunlight.

Eren even catches them out at a cafe once, where Erwin had cheerfully offered Eren to join them for lunch; that was the first time he sat down with them and got to know them. They were both in their 30s, having moved to better take care of Erwin’s aging father, who stubbornly refused to move into age care. Levi worked for a designing corporation and works online, while Erwin works an office job for the same company - they have no kids, have been happily married for nearly ten years, and have no plans of leaving soon.

And God, is Eren smitten. It doesn’t take long for him to spill the details to his two closest friends, who just roll their eyes endearingly and listen to Eren go on about the married couple next door who he has lunch with once a week, and maybe tea with Levi if he's feeling up for it. Eren makes extra effort to hide his toys away when he starts noticing the flirty looks he gets from both men, dressing just a little nicer and trying different colognes until Levi compliments him on the scent he’s wearing.

Mikasa, on one of her many visits, notices the subtle changes to his apartment and sits him down. “You remember what happened in your last relationship, right Eren?”   
  
He does, vividly - his last boyfriend had freaked out when he found out about Eren’s little side, had screamed harsh words and had nearly beaten him when Eren chased him out of his apartment in tears. It wasn’t long after Erwin and Levi had moved in, actually, and Levi had come out to figure out what all the commotion was with his usual scowl and bored tone. “What the fuck is- Eren?”   
  
Eren had quickly pulled himself up from the ground, where he had fallen after getting kicked in the stomach, and stepped away quickly from his now ex-boyfriend. Levi looks between them and quickly realises what’s going on, not even checking if his door is unlocked as he shuts it behind him, “You better fucking scram, you cunt, or you’re gonna regret it.”   
  
Eren’s ex quickly takes the hint and does as he’s told, not without spitting on the ground in front of Eren’s feet before stomping away. Levi looks at him with the most disgusted look on his face, which melts when he looks at Eren. He’s more vulnerable than Eren has ever seen him before, and it’s the first time it makes his heart skip a beat, “You alright, kid?”

“Y-Yeah,” Eren shakily says, sucking in a breath. “I think… I gotta call my sister, actually.”   
  
“Okay,” Levi murmures. “Listen, I know you don’t know us well, but Erwin and I are home from work today. If you need us, you can knock on our door.”   
  
Eren looks at him with surprise, knowing the man to not be very open to others, and sees a man older than himself shifting his feet awkwardly. Levi clearly doesn’t know what he’s doing but wants to help Eren somehow, and the gesture hits him  _ hard,  _ and he stutters out something he can’t recall now before tripping back into his apartment and stumbling for his phone. 

He’s a mess for the next week, finding himself wholed up in his apartment and into little space the majority of the time, often ignoring his needs to sleep instead. Erwin must realise two days after how affected he is, assuming Levi told him, and stops by in the morning to drop off a plastic bag of groceries.

“It’s not much, but it’s everyday things.” Erwin says as he leaves it just inside the front door, since Eren is too surprised to take it himself. “I don’t mind shopping for you, Eren. Levi told me what happened and you need time to recover.”   
  
He stops by every morning with the same plain bag, until a week later, Eren meets him in the elevator on Erwin’s way out, falling back into their usual routine. Erwin has a surprised look on his face when Eren hastily steps in between the closing doors, but takes his arm with a solid grip, “Glad to see you out.”   
  
Eren flushes. “You too- I mean- fuck.”   
  
Erwin grins.

Eren can feel his face going red at the memory, and he sighs, “Of course I do, Mika… but it won’t be like that this time. If I’m upfront this time and they don’t like it, then I’ll be less hurt, okay?”   
  
She thinks it over, bites her lip and savours her sandwich before she nods, knowing she couldn’t do anything to stop her headfast brother. “I just worry for you, Eren, but I trust you. If you think you can handle it, then I believe you.”   
  
They don’t talk about it, and Eren spends the next few weeks falling more in love with the couple next door. He spends more time in little space, curled up in his apartment and daydreaming about the two older men taking care of him - Erwin changing his diapers and blowing kisses into his exposed stomach and Levi dressing him immaculately. He even goes as far as stuffing himself between pillows when he’s watching cartoons and imagining it’s really Erwin and Levi, hugging him tight and keeping him warm so he falls asleep peacefully.

He wakes up one morning, television dark despite the movie he had been watching the night before, to a knock on the door. Eren doesn’t think about it as he gets up and opens it, blinking and squinting his eyes to the bright light outside, taking a few seconds to register Erwin at his door. He tries to say his name, only for the sound to come out muffled behind the binky he apparently still has in his mouth - suddenly his face is going red at the realisation, matching the surprised look Erwin is sporting, and slams the door in his neighbors face before he can think about it.

“Oh my god,” He whispers, back against the wood as the pacifier falls to the ground. There’s a beat of silence before there’s a softer knock at the door, and Eren’s heart picks up rapidly. “Go away!”   
  
“Eren, it’s fine-”   
  
“It’s not, it’s  _ weird,  _ and you weren’t meant to see that!”   
  
An audible sigh makes its way through the obstacle between them. “Sweetheart, I promise it’s not weird, okay? Please open the door.”   
  
“...Did you just call me sweetheart?”   
  
It’s hard to tell the tone of Erwin’s voice, since it always sounds so warm and inviting, but Eren likes to think there’s a touch of affection in there when he says, “I did.”   
  
“But… Levi-”   
  
“We have been pining after you for weeks now, Eren. I’m sure you’ve noticed.”

“Oh.” Eren’s voice comes out softer, slowly standing up and peeping through the eyehole. “You’re sure it’s not weird?”   
  
Erwin smiles, “I promise it’s not weird, Eren.”   
  
He slowly cracks open the door, standing back when Erwin walks in and refusing to meet his eyes, feeling his face burn with embarrassment. Erwin leans down and picks up the binky that falls on the floor, frowning at it and then pulling out his phone, “Is it okay if I call Levi?”   
  
“...Okay.”   
  
Erwin smiles at him happy and brushes his hair out of his face, “Thank you for trusting me, sweetheart.”

Eren stands between the back of the couch and the open door, not knowing what to do as he watches Erwin go to the sink and wash his pacifier, his phone between his ear and shoulder as he presumably speaks to Levi. The other man is over within thirty seconds, standing in the open door and looking at Eren with confusion, coming in and finally shutting the door. “What’s going on?”

Erwin comes back over, taking Eren’s head gently and popping the dry rubber back in Eren’s mouth, who briefly panics. His feeling flies down to his stomach when Erwin is suddenly leaning down and pulling Eren into his arms bridal style, the younger man scrambling for Erwin’s broad shoulders. Levi stands closer, “Ah, I see.”

Eren goes red, looking between the two of them rapidly. Erwin squeezes him gently, “Have you eaten?”   
  
He slowly shakes his head, and Levi takes that as his cue to move to the kitchen. Erwin follows and places Eren down onto one of the island stools, staying close and playing with his hair as they both watch Levi look through the cupboards and fridge. 

He turns while holding a carton of eggs. “How do you like your eggs?”   
  
It takes Eren’s airy mind a few seconds to register that he has to take out the pacifier to speak, pulling it out with a satisfying ‘pop’ sound. “Scrambled.”   
  
Levi’s lips quirk slightly, almost a smile that has Eren’s heart skipping a few beats, taking out three eggs, a carton of milk and searching the kitchen for the right utensils. After Eren stares at the eggs with furrowed brows for a few silent moments, Erwin speaks up beside him, “Don’t worry, baby. Levi and I already had breakfast.”

Eren nods up at the man, pillowing his head in his pecs when Erwin pulls him closer, sighing at the fingers threading his messy hair and nearly dozing off. He hadn’t realised Erwin had been humming some songs to produce sound in the kitchen, the rumbling of his chest soothing Eren and the last of his worries.

Suddenly, there’s a plate set in front of Eren, and his breath hitches; Levi had obviously found the dining sets he has hidden away just for these moments, having plated the eggs and what looks like bacon bits in one of Eren’s baby plates. He’d picked out the matching blue fork and spoon, with the little gloved hands on the ends, and it makes Eren tear up slightly. 

Erwin notices, “Eren? Is this okay?”   
  
He looks up at Erwin and nods, opening his mouth obediently when the man pulls his binky out and carefully sets it aside. Eren almost moves to take the utensils, but Levi is faster, leaning over the island and scooping up some of the food with the spoon, holding it out to Eren invitingly. He stares in awe for a few seconds, jolting when Erwin shakes him gently. "Do you want Levi to feed you?"

"...Yes please."

Levi doesn't make the encouraging noises like a parent would to a toddler, feeding Eren with a small smile permanently on his face. He cleans the corners of his mouth with some paper towel every few bites, and at one point holds Eren's chin to feed him more precisely. When the plate is clear, Eren’s whole body is warm with delight, stomach full and heart floating from the amount of love he feels for these two men. Levi rubs a thumb over Eren’s cheekbone, “You did really good, Eren.”   
  
A whimper digs its way out of Eren’s throat, and he flushes in embarrassment at the noise, hastily grabbing for the pacifier and shoving it back in his mouth. Levi snorts and Erwin chuckles, smoothing a hand down Eren’s back continuously, while Levi quickly washes the plate off and leaves it to dry on the rack by the sink. Eren grips the counter in his hand tightly before pulling the paci back out, “I think I might shower.”   
  
Levi leans on the counter, “Do you want us to stay?”   
  
Eren nods quickly, “Yes, I… we should talk about this. I made sure I didn’t slip too far so we could.”   
  
Erwin steps away, helping Eren off the stool even though they both knew he didn’t need it, and then grabs Erwin’s shirt when he tries to go to the living room, “Can you… pick out my outfit? Please?”   
  
Erwin smiles and steps back to gently kiss Eren’s forehead. “Of course we can, darling. Would you like us to set it out on the bed for you?”   
  
Eren nods, dipping into the hall to grab a towel before making his way to the bathroom, which was right next to the only bedroom in the apartment. He’s too distracted with ignoring the urge to have a bath instead to hear Erwin and Levi talking in the living room, staying in longer than he usually does to wash himself carefully. He dries off completely to not drip water down the hall, practically racing into his bedroom and shutting the door even though he knows Levi and Erwin wouldn’t care to see him.

On the bed is his bear onesie set out, along with a pair of boxers and a thin shirt - obviously they realise it’s too warm in this spring weather to wear proper pajamas under the thick overalls, but he doesn’t mind. He debates getting himself into a diaper but he knows he’ll be immensely frustrated if he does, hating putting his own diapers on, so insteads gets dressed into what’s set out.

Levi and Erwin are, predictably, sitting on the couch with the tv on at low volume, cuddling together and talking quietly. They pause when they spot Eren standing in the doorway and, without thought, separate and invite the younger in between them. Eren excitedly pads over and falls in between them, grinning when they scoot closer so there’s little to no room between them, and he sighs, “Thank you.”   
  
“What for?” Erwin asks, voice low as to not break the mood, sending shivers down Eren’s spine.

He shrugs, ignoring the urge to throw his thumb in his mouth; he’s so used to doing it when having a proper conversation with Mikasa and Armin, knowing they wouldn’t mind, that it’s a hard urge to resist. “Taking care of me? Not thinking it’s weird?”   
  
Levi sighs, “God, was that guy I met a few months ago your last boyfriend? Is this what he treated you like shit over?”   
  
“...Yes.”   
  
He doesn’t look surprised. “I would’ve beat him until he couldn’t move if I knew that.”   
  
“Levi…”   
  
Said man twists so he’s properly looking at Eren, who looks slightly scared at Levi’s sudden anger but not curling away, understanding it wasn’t directed at him. “I’m sorry you had to deal with that massive prick, baby, but I promise you we’re nothing like that. You’re Eren, and you’re loud and energetic and  _ God  _ do you have the worst taste in teas, but you’re you. And Erwin and I  _ like  _ you, okay?”   
  
Eren is most definitely crying now. Erwin is instantly over him, taking his cheeks and rubbing the fast-falling tears away, “Oh, sweetheart…”   
  
He sniffles, now  _ actually  _ stuffing his thumb in his mouth to hide his cries and lets himself get pulled into Erwin’s lap - their minimal height difference makes it so Eren can easily tuck his face into Erwin’s neck, wrapping his legs around the bigger man’s waist with ease. Levi gets up and returns a few minutes later with his “forest king” lion sippy cup, filled with warm milk, and one of Eren’s many worn plushies. He chuckles when Eren instantly reaches both hands out, having been turned by Erwin so his back is pressed to that thick chest, matching arms secured around his waist.

Levi has a small smile, one that sends butterflies to Eren’s stomach, which flutter faster when he opens his mouth. “Which one, baby?”   
  
Eren takes the plush, settling it in his lap before carefully holding the handles of his cup and pulling out the straw, “...I like that.”   
  
“Hm?”   
  
“You calling me baby,” Eren mumbles, feeling his cheeks redden when they both look at him and quickly stuffing his mouth with the straw. Levi sits back down, scooting closer so he’s right against Eren’s front, lanky legs pulled into his lap by firm hands.

Erwin speaks for them both, “Good, because we like the idea of you being our baby.”   
  
Eren giggles. It feels so easy to slip into this headspace with them around, feeling comfortable as they fuss around him. They turn on the television to something Eren has prerecorded, but he’s not paying attention, hyperfocusing on Levi’s hands feeling up his calf muscles and Erwin’s thumb rubbing over his hip bone; he’s so out of it that he doesn’t notice the pair talking to him at first.

When green eyes finally look at Levi, he’s smiling, “You’re really deep now, huh.”   
  
Eren nods, shifting slightly, “It’s been a while…”   
  
“Well, then what does our little boy want?” Erwin asks.

After a few seconds of thought, Eren is pulling the cup away from his mouth, his voice no longer coming out as a wet gurgle, even though the couple didn’t mind one bit. “Cuddle. And nap.”   
  
“I can always go for a nap,” Levi groans. He easily takes the sippy from Eren and sets it aside, and easily, they’re maneuvering until they’re all lying on the couch; Erwin is on his back, the other two between his muscular thighs, with Eren’s head high on his chest, and Levi’s cradled in Erwin’s elbow, looking like he belongs there.

Eren clutches his plush close to his heart, snuggling closer and sighing. He can already feel himself drifting off, and whoever’s hand that comes up to play with his hair isn’t helping.

“Sleep well, sweet boy.”

Eren doesn't know who says, nearly asleep when the voice reaches his hazy mind, but he smiles and slumbers.

**Author's Note:**

> check out my aot twitter? [<3](https://twitter.com/eggeren_art)  
> 


End file.
